1. Field of the Invention
The present invention relates to a printer that has a medium loading chamber that houses a recording medium on which a latent image can be formed by exposure and made visible by development, in which an image is recorded on a recording medium in the medium loading chamber by forming a latent image on the recording medium by exposure based on image data and developing the latent image.
2. Description of the Related Art
Some of printers of this type use an exposure head to form a latent image on an instant film sheet.
The exposure head has light emitting elements emitting red light, green light and blue light, respectively. A latent color image is recorded on an instant film by adjusting the quantity of light emitted by each light emitting element by a corresponding shutter in a liquid-crystal shutter array. The adjustment by each shutter in the liquid-crystal shutter array involves controlling the opening time, that is, the shutter speed of the shutter to provide a color gradation on the instant film according to the quantity of red, green or blue light received thereon when the shutter is open.
Printers provided with such an exposure head are used in various areas of various ambient temperatures or regardless of season. The printers used at different ambient temperatures may record images with varied gradations on recording media.
Thus, in order that the printers offer similar performance at different ambient temperatures, they have a look-up table for temperature compensation that enables images to be recorded with equal quality.
Even if the temperature control is conducted by the technique described above, if the printer outputs images successively after the printer is turned on, the temperature detected by the sensor at the time of turn-on may not be related to the current temperature of the exposure head, and thus, a blurred image may result. To avoid this, a temperature sensor may be provided on the exposure head to detect the temperature of the exposure head before exposure. However, providing the temperature sensor on the head results in an increase in size of the exposure head.
Besides, to address such a problem, according to another approach, the temperature control is achieved using a cooling mechanism without using the temperature sensor (see Japanese Patent Laid-Open No. 2000-302325). However, providing the cooling mechanism results in an increase in size of the entire apparatus.